a) Field of the Invention
The present invention relates to a laser leveling system, apparatus and method particularly adapted for use in construction projects, and more particularly for construction projects where it is necessary to position a variety of components of the building structure at various locations and at specific height locations (e.g. cabinets, bookshelves, countertops, etc.).
b) Background Art
There are numerous situations in the construction industry where it is necessary to ascertain elevation locations, and also to locate various components at precise elevations. This is a task that confronts surveyors, carpenters, brick layers, and others.
The surveyor commonly uses a leveling instrument which is mounted to the top end of a tripod so as to rotate about a vertical axis while maintaining its horizontal orientation within close tolerances. Also, a conventional surveyor""s transit will commonly be designed to function as a leveling instrument. These surveying instruments are usually used to place the foundation and possibly other elements of the building at the proper location and elevation. Then, as the more specific components are put into place, other locating and leveling techniques are commonly used.
A typical example is where a carpenter or cabinet maker is installing cabinets, countertops, bookshelves, etc. A common technique is to use chalk lines where a vertical elevation is established, such as measuring up a certain distance from the floor level. Then the countertops, cabinets, and other components are positioned using this chalk line as a elevation reference. The chalk line can be positioned by use of establishing one vertical location, and then using a carpenter""s level to align the chalk line horizontally. Another method is simply to establish two vertical locations independently (e.g. by measuring ascertain distance up from the floor level at different locations), then making elevation marks, and stringing the chalk line between the marks.
For a number of decades, optical tooling has been used to establish locations and also elevations. Within more recent years, laser instruments have been utilized for this purpose. A search of the patent literature disclosed various concepts relating to the use of laser instruments in establishing elevations and performing other functions. These are as follows:
U.S. Pat. No. 5,566,459 (Breda) shows a laser sighting device in a housing provided with spirit levels so that the device can be leveled and aligned. There are optical elements provided so that a beam can be projected in the desired path.
U.S. Pat. No. 5,533,268 (Keightley) shows a laser sighting device that xe2x80x9cdrawsxe2x80x9d a line in both a horizontal and vertical path for use in compound surfaces such as large chemical reaction chambers. The mirror is adjusted in two planes as it rotates.
U.S. Pat. No. 5,272,834 (Key) shows a surveying device which is mounted to a tripod and in which the user can observe alight beam on the surface of surveyor""s rod 14.
U.S. Pat. No. 4,718,171 (Schlemmer) shows a rotating laser beam system in which the laser beam is projected onto a staid which is provided with optical sensors 7 that provide an indication of height displayed in an output 3. This also is mounted to a tripod.
U.S. Pat. No. 3,588,249 (Studebaker) shows a right angle rotating light directing means such as a mirror or pentaprism 82. The light directing means is mounted on a rotating hollow shaft through which a laser directs light straight upward to the right angle directing means. The device is secured to an easily adjusted leveling means, and it is shown being mounted to a mobile vehicle and also to a tripod.
U.S. Pat. No. 2,661,653 (Castiglia) shows a light projecting device which is provided with a bubble level 6, that allows the device to be aligned. The device is provided with a housing that can be rotated by hand to point in any direction. The light beam is aimed at a target placed on a floor, and as the target is moved the misalignment of the floor can be measured. The device of course could be used as is the instant invention to establish alignment points on a wall or the like.
U.S. Pat. No. 4,183,667 (Denton) shows what is called a xe2x80x9clight-ray indicatorxe2x80x9d and is supported by a universal joint, with a weight at the lower end so as to seek a plumb line.
The following five patents also relate in general in laser/optical leveling devices, and deal mostly with improvements to the leveling apparatus itself. These are the following:
U.S. Pat. No. 5,539,990 (Le)
U.S. Pat. No. 5,212,889 (Lysen)
U.S. Pat. No. 4,854,704 (Funazaki et al.)
U.S. Pat. No. 4,679,937 (Cain et al.)
U.S. Pat. No. 3,771,876 (Ljungdahl et al.)
To the best knowledge of the applicant herein, while various precision leveling instruments have been available for many, many decades (and even centuries), and although optical/laser leveling devices have also been available for decades, many tasks that are performed on a day to day basis in the construction industry where it is required to establish height elevations within reasonably close tolerances do not employ these types of instruments. Rather, the use of chalk lines, carpenter levels, tape measurers (measuring a vertical distance from a base location), etc. continue to be commonly used.
A typical instance is where a skilled carpenter or cabinet maker is installing cabinets, countertops, bookshelves and other articles. In large part, the more sophisticated leveling instruments that have been available for many decades or centuries as well as the more recent optical/laser leveling systems, which have been available for many years, carpenters and cabinet makers in large part still rely on the simpler methods as indicated above (plumb lines, leveling instruments, measuring from floor level, etc.).
Accordingly, it is an object of the present invention to provide a system, apparatus and method which incorporates a laser instrument where there is a balance of desirable features which makes it particularly convenient, xe2x80x9cuser-friendlyxe2x80x9d, and efficient, and also a system where the set-up and use at various locations can be accomplished quickly and easily.
The present invention was developed to meet this need.
The laser leveling assembly of the present invention is used to establish height locations at selected locations, and it is particularly adapted for use at a location where there is a lower upwardly facing support surface and an upper downwardly facing bearing surface, such as a building structure having a floor support surface, and an upper bearing surface, such as an upper section of a doorway, a ceiling or an upper panel or member.
The laser assembly comprises a laser instrument to transmit a horizontally directed laser beam at laterally spaced locations to indicate a selected elevation or elevations at such spaced locations.
There is a mounting post having a longitudinal axis. This post comprises a lower contact end arranged to engage the lower support surface to establish a lower mounting location for the post. The post further comprises an upper contact end portion arranged to engage the upper bearing surface to establish an upper mounting location for the post so that the post can be positioned between the upper and lower locations so as to have a substantial vertical alignment component. Also, the mounting post provides a guideway extending along the longitudinal axis.
There is an instrument mounting device mounted to the post for movement along the guideway to a selected height position or positions. The mounting device is arranged to support the instrument in an operating position where the instrument can transmit the laser beam toward laterally spaced locations.
In a preferred form, one of the contact ends of the post is longitudinally adjustable so that the contact ends can be moved toward and away from one another. More particularly, in the preferred form the post comprises a first elongate post section connecting to the first contact end portion, and a second post section telescopically engaging the first post section and having the upper contact end.
The mounting device in the preferred form comprises a post engaging portion arranged to be fixedly positioned to the post and arranged to be able to move along the guideway of the post. There is an instrument mounting portion arranged to mount the instrument in its operating position. There is also an intermediate mounting portion connecting the post engaging portion and the instrument mounting portion.
In the preferred form, the intermediate mounting portion is arranged so that the instrument mounting portion can be located at different vertical locations relative to the post engaging portion.
In a preferred embodiment, the intermediate mounting portion comprises a support arm rotatably mounted so as to be able to rotate between an upper arm position to support the instrument mounting portion in an upper location and a lower arm location to support the instrument mounting portion at a lower location. More specifically, the intermediate mounting portion comprises a laterally extending offset mounting member to locate the instrument mounting portion at a location spaced laterally from the mounting post so that the instrument mounting portion would be able to move clear of an object located closely adjacent to the mounting post.
In a specific form, the intermediate mounting portion comprises a vertically oriented mounting member to be able to support said instrument mounting portion at height locations spaced laterally from the post engaging portion. The vertically oriented mounting portion is adjustable so as to be able to position the instrument mounting portion either above or below the elevation of the post engaging portion.
As a further feature, the mounting post has an elevation indicating portion positioned along the longitudinal axis of the post to indicate vertical location relative to the post. The mounting device has a height indicating device positioned to enable height location of the mounting device to be determined. In a preferred form, the elevation indicating portion has indicia increasing from a lower location to an upper location to indicate distance from a lower location, and also indicia increasing from an upper location toward a lower location to indicate distance from the upper location to the lower location.
The mounting device in a preferred form comprises a post engaging portion extending at least partially around the post, and providing a height indication device positioned adjacent to the distance indicating portion. More specifically, the height indicating device is mounted so as to be vertically adjustable relative to the post engaging portion. More specifically, said height indicating device comprises a vertically moveable transparent member with a height indicator thereon.
There is a post locking and stabilizing device comprising a threaded rotatable member which is mounted to the post and which can be rotated into and out of locking engagement to insert a lateral force relative to said telescoping members when in locking engagement. The assembly further comprises an instrument mounting locking device which operably engages the mounting device and the post and which comprises a rotatable threaded member to come into locking engagement between said instrument mounting device and said post.
In the method of the present invention, the assembly as recited above is employed. The laser instrument is mounted to the instrument mounting device which in turn is mounted to the post. The post is positioned so that the lower contact end of the post engages a lower support surface, and an upper contact end portion of the post engages the upper bearing surface so that the post is positioned between the upper and lower locations so as to have a substantial vertical alignment component, with the post providing a guideway extending the longitudinal axis.
The laser instrument is placed at the proper location on the post, and the laser instrument is then operated to direct a laser beam toward the location (e.g. a wall) where the elevation is to be established. Then the mounting device can be raised or lowered, placed in upper or lower locations relative to the mounting device, and adjustments made to facilitate the directing of the laser beam to the appropriate height location.
Other features of the present invention will become apparent from the following detailed description.